Mining in Cornwall

Tin is a relatively rare metal, found in two parts per million (as opposed to copper's 70 parts per million and the abundant iron at 50,000 parts per million). It was very useful, however, for its workability and especially for the making of alloys, so any source was a valuable find. Large deposits were found in the Far East, Iberian Peninsula, and souther France, but we will confine this post to talking about Cornwall.

The earliest evidence shows that tin was being mined in at least 2150BCE, the early Bronze Age. Copper was also found there, along with some arsenic, lead, silver, and zinc, but tin mining has been the most consistent use of the mines for millennia. When a small amount of tin is added to copper, the resulting bronze is much harder than either and more useful. This made tin a more useful commodity than just using tin on its own, and a tin trade with the Mediterranean started long before even the Roman Empire. Herodotus mentions an area called the Cassiterides, the "tin islands," and Cornwall is thought to be the likeliest spot.

One of the oldest mines in Cornwall is the Ding Dong mine (the name may refer to the "head of the lode"). The picture above is a shaft at the Ding Dong. A local legend claims that the mine was visited by Joseph of Arimathea, tin trader and uncle to Jesus, who visited the mine with the young Jesus; not his only trip to Britain, since he later founded Glastonbury Abbey, etc. (There is, of course, no evidence, but that's what legends are.)

Curiously, Domesday Book doesn't mention Cornwall tin, but Henry II acknowledged it when he granted to Dartmoor, another mining location,

all the diggers and buyers of black tin, and all the smelters of tin, and traders of tin in the first smelting shall have the just and ancient customs and liberties established in Devon and Cornwall.

This indicates that Cornwall mining was "ancient" as of Henry's reign. Henry's son John granted a charter for the miners' rights, establishing stannaries that allowed the tin-mining community to administer its own laws, etc.

The mines produced an enormous amount: 650 tons in 1337, falling to "only" 250 tons during the Black Death, but rising to 800 tons by 1400.

Demand for tin decreased in the 20th century. Increased recycling efforts, as well as the use of aluminum for containers and the development of protective polymer lacquers to coat food containers hastened the closing of tin mines as unprofitable. One of the last tin mines in Cornwall to close was the South Crofty mine in 1998, Europe's last tin mine.

Fear not for Cornwall mining, however! The 21st century is finding reasons to re-open defunct Cornish mines for a substance as important to our time as tin was to the Bronze Age: lithium, an element vital to our battery-operated world. (Here is a link to National Geographic article.)

Going back to the Middle Ages, however, I want to talk about another substance, made with tin, that was so associated with daily use in the Middle Ages that a 19th century revival of interest in the Middle Ages made this substance much in demand. Check back tomorrow and we'll learn more about the lovely, useful, and toxic pewter.

Stannaries

A stannary was an administrative division in the counties of Cornwall and Devon based on tin-mining. The term comes from Middle English stannarie based on Medieval Latin stannaria, "tin mine,"which itself is from the Latin stannum, "tin." (You may know that the chemical symbol for Tin is Sn; now you know why.)

Tin was so important that a body of law was developed to deal specifically with stannaries. King John in 1201 gave the tin miners of Cornwall the Stannary Charter: the right to prospect for tin anywhere, to be exempt from standard taxation, and to have their own stannary courts in the case of law-breaking. King Edward I in 1305 confirmed these rights, as did Edward III when he created the Duchy of Cornwall in 1337. Crockern Tor, pictured above, was the site of the Stannary Parliament, representing the tin industry.

Tin mining pre-dated the Middle Ages in Cornwall. When the Romans arrived, it was already thriving. Diodorus Siculus in 44BCE wrote the earliest reference to Cornwall we know:

The people of that promontory of Britain called Belerion [west Cornwall] are friendly to strangers and, from their contact with foreign merchants, are civilised in their way of life. They carefully work the ground from which they extract the tin.

In the Middle Ages, the tin was smelted and made into blocks (later standardized at 170 kilograms). They were taken to specifically designated locations called stannary towns where a "prover" would test it for quality, then put an official stamp on it and allow it to be sold. A duty would be calculated on the sale, equivalent to four shillings per hundredweight (170 kilograms = 3.34 hundredweight) under Edward I. Duty amounts changed over time, but the amount of tin coming out of Cornwall and Devon was considerable, so anyone given the right to the duties could have a hefty income. After King John died (and after some other events), the king's council allowed his widow, Isabella of Angoulême the duty from the stannaries of Devon.

This whole system of special privilege, etc., existed until the Tin Duties Act of 1838.

The history of mining in Cornwall was far more extensive than dealing with tin, even tied to a Biblical legend. I'll tell you more next time.